CVE-2026-3104

HIGH 7.5

Memory leak in code preparing DNSSEC proofs of non-existence

CVSS Score

7.5

EPSS Score

0.0%

EPSS Percentile

0th

A specially crafted domain can be used to cause a memory leak in a BIND resolver simply by querying this domain. This issue affects BIND 9 versions 9.20.0 through 9.20.20, 9.21.0 through 9.21.19, and 9.20.9-S1 through 9.20.20-S1. BIND 9 versions 9.18.0 through 9.18.46 and 9.18.11-S1 through 9.18.46-S1 are NOT affected.

CWE	CWE-772
Vendor	isc
Product	bind 9
Published	Mar 25, 2026
Last Updated	Mar 25, 2026

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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Affected Versions

ISC / BIND 9

9.20.0 ≤ 9.20.20 9.21.0 ≤ 9.21.19 9.20.9-S1 ≤ 9.20.20-S1

References

NVD ↗ CVE.org ↗ EPSS Data ↗

kb.isc.org: https://kb.isc.org/docs/cve-2026-3104 downloads.isc.org: https://downloads.isc.org/isc/bind9/9.20.21 downloads.isc.org: https://downloads.isc.org/isc/bind9/9.21.20

Credits

ISC would like to thank Vitaly Simonovich for bringing this vulnerability to our attention.